Fix indentation

Fix indentation in the test.
diff --git a/tests/suites/test_suite_nist_kw.function b/tests/suites/test_suite_nist_kw.function
index 5d0cd80..ae3ef80 100644
--- a/tests/suites/test_suite_nist_kw.function
+++ b/tests/suites/test_suite_nist_kw.function
@@ -167,7 +167,7 @@
     if( out_len != 0 )
     {
         ciphertext = mbedtls_calloc( 1, output_len );
-    TEST_ASSERT( ciphertext != NULL );
+        TEST_ASSERT( ciphertext != NULL );
     }
 
     memset( plaintext, 0, in_len );